A battery or batteries are generally used as a power supply unit for a portable terminal unit, and the batteries are accommodated in a battery case. There are various types of battery case for a portable terminal unit, and some of them are incorporated in a basic body of a portable terminal unit, while the others are attached to or detached from a basic body of a portable terminal unit.
FIG. 3 is a perspectively view illustrating an example of a conventional type of battery case for a portable terminal unit. This battery case comprises a battery storage case 2 in which four batteries are accommodated, an accommodating section 5, for accommodating the battery storage case 2, provided on a rear surface of a basic body of a portable terminal unit 3 in the side facing the case, and a battery cover 6 which is a cover for this accommodating section.
The battery storage case 2 is a box in which two batteries can be set in along the vertical direction in the figure, and the batteries set therein are sustained between a - (minus) side spring 7 and a + (plus) side contact arranged in the storage case 2. The battery storage case 2, with batteries set therein, is stored in the accommodating section 5 of the portable terminal unit 3, and is covered by a battery cover 6. The cover 6 is fixed by engaging a convex section 9 of the cover 6 in a concave section 10 arranged in the portable terminal unit 3.
In this type of battery case as described above, as the battery storage case 2 is used, the portable terminal unit 3 becomes larger by a wall thickness t (approx. 4 mm) of the storage case. It is disadvantageous for the width W of the portable terminal unit 4 to become larger. It is also disadvantageous for the number of parts forming battery storage case 2 to increase.
FIG. 4 is a perspective view illustrating another example of a conventional type of battery case for a portable terminal unit. This battery case shown in FIG. 4 similar to the one shown in the example of the conventional type shown in FIG. 2, but is different from the latter in that the longitudinal direction of the battery 1 is parallel to the longitudinal direction of the portable terminal unit 3 when the battery 1 is accommodated in the portable terminal unit 3. At a bottom section of the portable terminal unit 3 is provided an accommodating section 12 to accommodate therein the battery storage case 2. A battery cover 13 for covering the opening of this accommodating section 13 is slid when inserted into the opening.
With this conventional type of battery case, the width W of a portable terminal unit can be reduced, but because of the length D of the battery storage case 2, the total length L of a portable terminal unit becomes disadvantageously longer.
FIG. 5 is a perspective view illustrating another example of a conventional type of portable terminal unit. This battery case comprises a front battery storage case 14 in which two batteries can be accommodated, and a rear battery storage case 15 in which also two batteries can be accommodated. In the side where the front battery storage case 14 and the rear battery storage case 15 engage the bottom section of the portable terminal unit 3 are provided slender concave sections 16, 17 for sliding movement. On the other hand, at a bottom section of the portable terminal unit 3 are provided slender convex sections 18, 19 for sliding movement.
In the conventional type of battery case as described above, two batteries are set in the front battery storage case 14 and the rear battery storage case 15 respectively, then openings of the cases are overlaid, and the concave sections 16, 17 are slid in the direction indicated by an arrow mark 20 and connected to the convex sections 18, 19 in the bottom section of the portable terminal unit 3. The storage cases 14, 15 thus are attached to the portable terminal unit 3.
In the conventional technology described above, a battery case is not incorporated in the portable terminal unit 3, but is detachably attached to the latter, so that there are some restrictions in designing the portable terminal unit 3, and also as the battery case is divided into two portions, the number of parts disadvantageously increases.
In addition, it has been impossible to provide any other member used in the portable terminal unit such as a speaker in the battery case, and an additional space is required for accommodation such additional members, which makes it difficult to minimize a size of the unit.